about 7:43 with an investigation to what really happens to your clothing when you drop it off at the dry cleaner's. ABC chief business correspondent Rebecca Jarvis here with the details. I think we're surprised by what you found. As was I. Turns out there is good reason for that old expression getting taken to the cleaner's so what happens after you leave your cleaner with your pose valuable clothes. Take a look. You hand the dry cleaner's your most precious your most irreplaceable garments and what do you get back. You shrunk it. Reporter: Not always what you thought. Annoyance at the dry cleaner's so common it shows up in movies. Crazy, a fool. They don't have the best reputation. Reporter: Jerry Pozniak runs jeeves but today he's letting us in on the dirty little secrets of the industry. Makes you angry. It does make me angry. Reporter: Secret number one sh, sc scummy sol vent. Dry cleaning is a mystery for most of us, the key to the process is this, the sol vent. It's supposed to run clear as a mountain stream. Except he says when some dry cleaner's cut corners and increase profits, by neglecting to filter the solvent enough leaving this gunk in with your clothes. That's what my clothes would be laundered in. Dirty solvent. This is the bottom residue of dirty solvent. It's kind of like if you were taking a bath and you have bath water and five other people took a bath before you then you got into that water, would you feel clean when you came out? Reporter: And secret number two, jerk revenge. Jerry says most customers are great, but if you act like a jerk, he's heard of places that will only pretend to clean your clothes. Now we decided to turn the tables and we brought ten shirts and ten pairs of pants with identical stain, mustard, wine and nail Polish to ten different dry cleaners and you're not going to believe what we found. More on my report and other true confessions coming up. Oh. Come on. But, guy, this is why, the dirty bathwater. There's so much more to this coming up tomorrow on "20/20." We'll watch but during the commercial, you tell us.

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